水稻冠根发育调节因子WOX11互作蛋白的鉴定及作用机理研究

Rice is a globally important food crop. It has both scientific and applied value to indentify the functional genes that associate with grain high-yield, nutrient high-effiency, and stress resistance. The root system, which consists of different types of root, play important roles in anchoring plant, nutrient and water uptake, meanwhile to determine the growth of above-ground part, crop productivity, and resistance to envienmental stress. The crown roots are a major component of the fibrous root architecture of rice，and grow acropetally along both the main stem and the tillers to keep pace with leaf emergence. Thus, Crown root is major organ that acquisited water and nutrients during the growing period. Therefore determines the crop growth and productivity, as well as the resistance to abiotic stresses. WOX11, identified by our group, is a major factor that regulates crown root development. Previous studies showed that WOX11 specifically expressed in developing crown root, and involved in root elongation growth via plant hormone, auxin and cytokinin signalling pathway. The major goal of the present proposal is to indentify the WOX11-interacting proteins, investigate the function of the WOX11-interacting protein, as well as the relation of these downstream genes with plant hormones. The expected results will construct the regulatory network of WOX11, therefore uncover the molecular event of crown root development. The present proposal aims to provide the theory fountion and guidelines for the genetical improvement of root patternm increse of grain productivity, enhancement of resistance to advert stimuli, and high-efficency untility of nutrients such as nitrogen and potasium.

水稻是世界上最重要的粮食作物，寻找并鉴定与高产、高效和抗性相关的功能基因对水稻育种具有重要的理论意义和应用价值。由不同类型的根组成的根系是植物固着、吸收养分和水分的主要器官，同时也决定着植物地上部分的生长、产量和抗性。冠根是水稻根系的主要组成部分，决定着水稻生长、产量以及对不良环境胁迫的抗性。本课题组分离到的WOX11是调控水稻冠根发育的重要调节因子，研究表明该基因主要在水稻冠根发育中特异表达，且通过介导生长素和细胞分裂素信号途径调节水稻冠根的伸长生长。本研究的主要目的是鉴定WOX11在水稻冠根发育中的互作蛋白并探索它们参与冠根发育的生物学功能及其调控的下游基因以及它们与植物激素之间的相互关系，建立WOX11在水稻冠根发育中的调控网络，揭示水稻冠根的发育调控机理，为改善水稻根系的形态构型，从而提高水稻产量、增加其对逆境胁迫的抗性和氮、磷营养的高效利用提供理论基础和依据。

水稻是世界上最重要的粮食作物，寻找并鉴定与高产、高效和抗性相关的功能基因对水稻育种具有重要的理论意义和应用价值。WOX11是本课题组分离到的调控水稻冠根发育的重要调节因子。本研究重点是鉴定与WOX11 互作的蛋白并解析它们在冠根发育中的生物学功能；探索WOX11及互作蛋白调控的下游基因并鉴定它们在冠根发育中的功能，进一步挖掘WOX11 与互作蛋白以及其他调控冠根发育因子及植物激素在水稻冠根发育中的相互关系，建立水稻冠根发育的调控网络。期望揭示水稻冠根的发育调控机理，为改善水稻根系的形态构型，从而提高水稻产量、增加其对逆境胁迫的抗性和氮、磷营养的高效利用提供理论基础和依据。针对上述研究目的，我们按照申请书上既定的研究计划设计了一系列实验，取得了一些成果。我们进一步解析了WOX11在冠根发育中调控下游基因的分子机制。在细胞分裂素途径中我们的研究结果表明WOX11和AP2类转录因子ERF3互作在冠根发育的不同阶段精细地调控细胞分裂素信号，从而促进水稻冠根的起始、延伸和伸长。在冠根分生区细胞增殖过程中WOX11会招募组蛋白乙酰转移酶复合体（SAGA， ADA2-GCN5）通过改变染色质修饰状态从而促进一系列基因的表达。除此之外，WOX11可以促进水稻对内囊藻素、干旱和低钾的抗性，从而潜在地增加水稻的产量。